The present invention relates to persistent storage capacity management. More specifically, the invention relates to one or more processes for space savings impact analysis and evaluation and for execution of a space saving technique.
Compression and thin provisioning are techniques used in data centers to reduce storage capacity usage, also known as a storage footprint, thereby making more storage available. Storage administrators can specify whether a storage volume is compressed, thick, or thin, per a management policy not only at initial provisioning time but also during steady state lifecycle. However, reducing storage capacity using any of the above techniques may have a negative impact on application performance. For example, reading from a compressed storage volume requires the volume to be subject to a de-compression technique, which requires additional processing. At the same time, reading from a thinned volume may also require additional processing, such as metadata lookup prior to data access. Reading data from either a compressed volume or a thinned volume introduces I/O latency.
There is a balance between performance of data storage techniques and application of data storage techniques. Performance impacts and capacity savings are functions of a workload and vary widely across different workload types. For example, compressing or thinning a volume has a minimal benefit if there is ample available space in the storage pool in which the application volume resides. As such, storage footprint reducing techniques, such as compression and thin provisioning, are desirable for application to free up storage capacity in storage pools that are near or have surpassed a capacity threshold.